Researcher Maria Mroz, of Newcastle University, surveyed 829 early-years workers for the Nuffield Foundation. She found that nine out of 10 had had no post-qualification training in speech and language work.
She also found that almost a third had sought help about language disorders from informal sources, such as magazines, friends or relatives with specialist knowledge or through experience with their own children.
A follow-up study of 50 workers found that 46 wanted training in speech and language.
Ms Mroz's report says: "The roles of an early years professional are multiple but it is clear that talking and playing are not as prominent as one might wish in terms of developing children's language.
"Early-years professionals are united in recognising their broad responsibility to assess all of the children in their setting. "However, they lack tools and knowledge to specifically assess speech and language development and to identify delay or disorder."
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